Excerpted from the README file: Term::Query.pm is a Perl 5 module, which performs generalized queries on various kinds of values. Validation and normalization of input, based on the type, is automated, as is error reporting and re-solicitation of input. Input of '?', unless configured otherwise, provides useful, helpful information, based on the expected input type, even in the absence of a programmer-supplied help string. WWW: http://search.cpan.org/dist/Term-Query